The present invention relates to a trolling motor mount for fishing boats operated at low speed by one or more trolling motors. The present invention also relates to boats which operate through use of a main motor at higher operating speeds and which utilize trim tabs to fine tune the orientation of the boat at the higher running speeds.
Boats used for sport fishing often utilize one or more low-powered trolling motors directly mounted onto the rear transom of the boat on one or both sides of the high-powered main motor. The main motor mounted to the transom is utilized to drive the boat when it traverses between port and the selected fishing area, or from one fishing area to another. When the boat reaches the desired fishing area, the main motor is angularly elevated out of the water, often by electrical and hydraulic means, and the trolling motors are angularly lowered into the water. The type of trolling motors commonly used often do not have electrical means to raise and lower the motor in and out of the water, thus necessitating the manual operation thereof.
Prior to or after trolling operation, the trolling motors are raised out of the water, the main motor is lowered into the water, and the boat is driven at higher running speed. During the higher speed operation, it is known to utilize planar trim tabs or plates attached to the bottom of the transom on each side of the main motor. Each trim tab is operated by a piston from an out-of-the-water position to a position whereby the planar tab extends down into the water. The extent that the planar tab extends into the water can be varied by the piston so that the front to rear and side to side orientation of the boat can be fine tuned while operating at higher running speed.
It is also known to mount the trolling motor directly on the top of the planar trim tab or plate, the plate then serving as both the trim tab in one position and as a trolling motor mounting in a second lower position. However, such a mounting system has not been found to operate satisfactorily for reasons including that the trolling motor is angled into the water, the trolling motor""s operation is partly obstructed, and the trolling motor cannot be positioned sufficiently below the surface of the water and in the proper orientation to prevent cavitation.
The invention disclosed in my prior patent, U.S. Pat. No. 5,842,895 issued Dec. 1, 1998 and here incorporated by reference, has overcome the deficiencies of the above-noted prior art. A trolling motor mount is disclosed in my prior patent whereby the trolling motor may be automatically rather than manually raised from, or lowered to, its non-obstructed full operation position immersed in the water at a sufficient depth to avoid cavitation. Further, a portion of the motor mount may be utilized as a trim plate when the trolling motor is automatically raised out of the water. The trolling motor mount of my prior patent includes a first planar plate having its front edge hingedly attached to the rear of the boat transom adjacent the bottom thereof. A second planar plate (or continuation of the first plate) has its front edge or end attached adjacent to the rear of the first plate, the second planar plate extending rearwardly at a predetermined substantial angle from the plane of the first plate. A trolling motor is attached to the bottom of the second plate. A controllable piston is connected between the top of the first plate and the upper part of the boat transom. When the boat is to operate at running speed under the power of the main motor, the first plate can be rotated about its hinge connection to the transom to a first position where the first plate will act as a trim tab or plate. In this first position, the second plate extends upwardly out of the water and consequently the trolling motor on the bottom of the second plate also extends upwardly out of the water. When it is desired to operate the boat for trolling, the main motor is turned off and elevated out of the water. The first plate is then rotated about its hinge connection to a second position lower than the first position extending sufficiently down into the water such that the second plate and trolling motor attached to its bottom are immersed at an approximately horizontal trolling position in the water. The first plate does not obstruct the operation of the trolling motor since the trolling motor is attached to the bottom of the second plate and is lower in the water than both the first and second planar plates. The trolling motor, by virtue of being attached to the bottom of the second plate, is also sufficiently below water line to avoid cavitation affecting the operating characteristics of the motor. Electrical control wiring extends from the trolling motor to control means in the boat.
The present invention is intended to add certain structural improvements and refinements to the trolling motor mount of my above-noted prior patent, while still maintaining the advantages of the same mode of operation. In the present invention, the trolling motor mount also may be automatically raised from, or lowered to, its non-obstructed full operational position immersed in the water at a sufficient depth to avoid cavitation. Further, a portion of the motor mount may be utilized as a trim plate or tab when the trolling motor is automatically raised out of the water.
The trolling motor mount of the present invention has a first plate-like member having a front end of predetermined width, and a rear end terminating in a rearwardly extending tongue of significantly narrower width than said predetermined width. The front end of the first plate-like member is hingedly attached to the rear transom of the boat adjacent the bottom of the transom. A second plate-like member, whose width may approximate the width of the tongue, has a front end attached to the first plate-like member at a position forwardly of the tongue for structural integrity. The second plate-like member overlies the tongue and extends rearwardly at a predetermined substantial angle from the plane of the first plate-like member. The second plate-like member preferably has downwardly depending sides, with the front of the second plate-like member attached (i.e., as by welding) to the first plate-like member, and portions of said downwardly depending sides being attached (i.e., as by welding) to both said first plate-like member and said tongue. A structural reinforcing beam or channel member may be attached to both the top of the first plate-like member and said tongue for further structural integrity of the mount. Said reinforcing beam also may provide connection points for pivotal connection of one end of a controllable piston to raise and lower the trolling motor mount, the second end of the piston being pivotally connected to the upper part of the boat transom.
The trolling motor is preferably attached to the underside of the second plate-like member. The width of the tongue preferably approximates the width of the trolling motor so that the flow of water to the blades of the trolling motor are not obstructed. The length of the tongue is likewise preferably such that when the trolling motor mount is in its down, operating position, the tongue length does not interfere with the flow of water to the trolling motor blades. The tongue also aids in weed-free operation of the trolling motor, and extends the water flow off the first plate-like member. The rearward end of the tongue is curved to assist in water flow in either the higher speed or trolling speed operations of the present invention.
When the boat is operating at running speed under main motor power, the first plate-like member can be rotated about its hinge connection to the transom to a first position where the first plate-like member will function as a trim tab. The second plate-like member as well as the trolling motor extend upwardly out of the water. When it is desired to operate the boat for trolling, the main motor is turned off and elevated out of the water. The first plate-like member is then rotated about its hinge connection to a second position lower than the first position extending sufficiently down into the water such that the second plate-like member and trolling motor attached to its bottom are immersed at an approximately horizontal trolling position in the water and at a depth to avoid cavitation affecting the operating characteristics of the motor. Electrical control wiring extends from the trolling motor to control means in the boat.